Grinding attachment for lathes



' Jan. 7, 1947. B WN 2,413,950

. GRINDING ATTACHMENT FOR LATHES Filed June 10, 1944 I4 6 w/OZI? AfiOZV/fmmvrm ATTORNEYS Patented Jan. 7, 1947 UNITED STATES PATENT OFFICE 3 Claims.

The invention relates to a grinding attachment, and more especial y to an automatically regulated grinding attachment for lathes or the like.

The primary object of the invention is the provision of an attachment of this character, Wherein the tool chuck for a tool to be ground is automatically regulated for causing the relief or clearance on such tool being ground, during the grinding operation thereof.

Another object of the invention is the provision of an attachment of this character, wherein it is readily and easily set or adjusted to control the relief or clearance periods of grinding operation in. a lathe.

A further object of the invention is the provision of an attachment of this character, wherein the working thereof is novel and its assembly-in a head stock of a lathe is unique, it being positive in operation and automatic in the working thereof.

A still further object of the invention is the provision of an attachment of this character, which is simple in construction, thoroughly reliable and eificient in operation, strong, durable, readily and easily adjusted, conveniently accessible, possessing few parts, thus minimizing costs in repairs thereto, if necessary, assured of accuracy in the control thereof, and inexpensive to manufacture and install.

With these and other objects in view the invention consists in the features of construction,

combination and arrangement of parts as will be.

hereinafter more fully described, illustrated in the accompanying drawing, which shows the preferred embodiment of the invention, and pointed out in the claims hereunto appended.

In the accompanying drawing:

Figure 1 is a top plan view of a head stock of a lathe showing the grinding attachment constructed in accordance with the invention applied thereto.

Figure 2 is a detail elevation, partly in section or broken away, of the chuck spindle.

Figure 3 is a fragmentary sectional view taken on the line 3-3 of Figure 1 looking in the direction of the arrows.

Figure 4 is a side view of the adjustable cam bracket detached.

Figure 5 is a bottom plan view thereof.

Figure 6 is a sectional view on the line 66 of Figure 2 looking in the direction of the arrows.

Similar reference characters indicate corresponding parts throughout the several views in the drawing.

2 Referring to the drawing, A designates generally the head stock of a lathe, the latter having its spindle it for the aid head stock axially displaceable within the latter, yet rotatable with the driving pulley unit H, this being effected by I an externally tapered bushing l2, having a straight internal diameter corresponding to the external diameter of the said spindle Ii) for accommodating the latter as a bearing therefor. This bushing 12 turns with the unit I l and is set with the said spindle H? in the bearing areas of the head stock, without axial displacement of the bushing with the said spindle.

On the bearing area [3 of the head stock A is a flat bed plate [4, which is bolted to this area as at I5, and upon this plate [4 is carried an adjustable cam bracket 16, which is of inverted substantially L-shape, its attaching arm l'l being pivotally bolted at I8 to the plate Hi, so that its cam wing it Will hang over the bearing area is into the path of a series of contacting members 29 fitted concentrically of the spindle It! in an annular flange 2! near the outer periphery thereof and at uniformly spaced distances apart from each other. This flange 2| is a part of the spindle H] which has a socketed chuck end 22 next to the said flange for receiving a cutting tool not shown.

The spindle it has its other end 23 tensioned by a coiled spring 24 acting thereon to retract the said spindle Ii! to have its flange 2i urged toward the cam wing 19. The spindle ill for that portion thereof within the bushing 12 has an elongated slot 25 receiving a cross pin 26 stationarily held in the said bushing 52, and in this manner the said spindle til will rotate with the bushing and willbe limited to longitudinal displacement therein for the axial movement of the said spindle under the influence of the cam acting against the contact members 20.

The cam bracket it in its arm IT has formed transversely thereof an arcuate shaped slot 21 in which is engaged a set screw 28 tapped in the bed plate l4, so that the cam wing it can be adjusted to increase or decrease the cam action thereof on the contact members 28) to advance the spindle it with a tool fitted thereto at the chuck end 22.

The contact members 26 acting on the cam wing l9 causes the spindle Hi to advance at proper intervals to grind relief on a cutter with any number of flutes ordinarily found, the contact members 26 striking the cam wing I9 in such a way as to cause the spindle IE) carrying the cutter to advance at just the right position in its rotation. In other words, the spindle HI is intermittently advanced by the cam action during the rotation of such spindle in the operation of the attachment for grinding countersinks, taps, and other small tools used in shipyards and other industries.

What is claimed is:

1. An attachment of the kind described, comprising a spindle for fitting a lathe head stock,

a slot in said spindle adjacent the other end 10 thereof, an externally tapered bushing having a straight internal diameter corresponding to the external diameter of said spindle mounted on said spindle over said slot a crosspin in said bushing coacting with said slot in said spindle Whereby said spindle will rotate and have axial movement in said bushing, a flange on said spindle adjacent said bushing, a plurality of spaced contact members on said flange concentric of and rotatable with said spindle, and cam means adjustably fitting the head stock in the path of the contact members for engagement therewith to effect intermittent axial displacement of the said spindle during rotation thereof.

2. The invention as in claim 1 wherein means is provided for adjusting the cam means on said headstock.

3. The invention as in claim 1, wherein means is provided for urging the spindle in a direction to have the contact members engage the cam 15 means.

JOHN E. BROWN. 

